Contrary to the negative acute-phase protein (APP) response, there is no consistent correlation between serum pentameric C-reactive protein (pCRP) and major depression (MDD). Monomeric CRP (mCRP), a dissociation product of pCRP under immune-inflammatory conditions, exhibits pro-inflammatory effects; however, it has not been investigated in MDD or its subtypes, major dysmood disorder (MDMD) and simple dysmood disorder (SDMD).

To examine serum mCRP, albumin, transferrin, M1 macrophage and Thelper-17 immune profiles, and adverse childhood experiences (ACEs) in MDD, MDMD and SDMD.

Seventy-nine MDMD patients, 30 SDMD patients, and 40 controls were included. Serum mCRP was measured by ELISA; albumin, transferrin, and pCRP by biochemical assays; and cytokines using Luminex technology.

MDMD patients showed significantly higher mCRP compared with SDMD and controls, while both patient groups exhibited reduced albumin and transferrin. Combining mCRP with albumin and transferrin showed an adequate accuracy for MDD (area under the ROC Curve = 0.793). Adding IL-17A and ACEs improved accuracy (ROC=0.855). Serum mCRP levels are additionally associated with pCRP, M1 macrophage profile, body mass index, and ACEs. Up to 36.6% of the variance in overall severity of depression was explained by mCRP, T-helper-17 profile, ACEs (all positively), albumin and transferrin (both inversely).

Future research in MDD should employ mCRP rather than pCRP as a biomarker of depression/MDMD. Combining mCRP with biomarkers of the negative acute-phase response identified 63.7% of MDD patients with a smoldering acute-phase response, with a specificity of 82.1%. We recommend to assess mCRP rather than pCRP in MDD studies.

Neuropsychiatric disorders in preeclampsia (PE) women are prevalent and worsen PE outcome. Immune-related biomarkers including soluble sCD80 and cytotoxic T-lymphocyte antigen-4 (sCTLA-4) are not well studied in relation to depression, anxiety, and chronic fatigue due to PE.

The aim is to study serum immune-inflammatory biomarkers of PE and delineate their associations with the Hamilton Depression (HAMD), Anxiety (HAMA), and Fibro-Fatigue (FF) rating Scale scores. sCD80, sCTLA-4, vitamin D, granulocyte-macrophage colony-stimulating factor, zinc, copper, magnesium, and calcium were measured in 90 PE compared with 60 non-PE pregnant women.

PE women show higher depression, anxiety and FF rating scale scores as compared with control women. sCTLA-4, sCD80, and copper were significantly higher and zinc, magnesium, and calcium significantly lower in PE women than in controls. Multiple regression analysis showed that around 55.8%-58.0% of the variance in the HAMD, HAMA and FF scores was explained by the regression on biomarkers; the top 3 most important biomarkers were sCTLA-4, sCD80, and vitamin D. The sCTLA-4/sCD80 ratio was significantly and inversely associated with the HAMD/HAMA/FF scores. We found that around 70% of the variance in systolic blood pressure could be explained by sCTLA-4, vitamin D, calcium, and copper.

The findings underscore that PE and depression, anxiety, and chronic fatigue symptoms due to PE are accompanied by activation of the immune-inflammatory response system. More specifically, disbalances among soluble checkpoint molecules seem to be involved in the pathophysiology of hypertension and neuropsychiatric symptoms due to PE.